中文摘要：

利用ANSYS有限元程序对大宽厚比H形截面轴压构件的极限承载力进行了非线性有限元分析。分析中考虑了材料非线性和初始几何缺陷的影响，通过变化构件尺寸、材料屈服强度等参数，对共计44个构件进行了分析。应用新兴的直接强度法和传统的有效截面法对构件的极限承载力进行了计算。结果显示：有限元计算结果与直接强度法计算结果及有效截面法计算结果比值的平均值分别为1．039和1．098。与直接强度法相比，有效截面法计算过程较繁琐，且结果略显保守。直接强度法起源于单轴对称截面冷弯薄壁型钢结构构件的承载力计算，分析表明用其对大宽厚比H形截面柱的极限承载力进行计算是可行的。

英文摘要：

The ultimate load-carrying capacity of columns under an axial load with a large width-to-thickness ratio and H-shaped cross sections was studied by a nonlinear finite element analysis using ANSYS program. The influence of the material plasticity and geometric imperfection was considered in the analysis. A total of 44 columns with different sizes, material yield strength and other parameters were analyzed. The ultimate load-carrying capacities of columns were also computed by using a direct strength method and a traditional effective section method. The results show that the average ratio of the results calculated by the finite element analysis to the direct strength method is 1.039; the average ratio of the results calculated by the finite element analysis to the effective section method is 1.098. Compared with the direct strength method, the effective section method tends to being tedious and lightly conservative. It indicates that it is feasible to calculate the ultimate load-carrying capacity of columns of H-shaped cross sections and large width-to-thickness ratios under axial loads by the direct strength method, originated from the ultimate load-carrying capacity calculation of cold-formed steel structure members with singly symmetric cross-sections.